Locomotive sanding control apparatus



June 16, 1942. c. M. me 2,286,680

' LOCOMOTIVE SANDING CONTROI; APPARATUS Filed April 29, 1941 2 sheets-sheet 1 Fig.1. I

INVENTOR CLAUDE M.HINES BY mug ATTORNEY June 16, 1942. c. M. HINES 6,

LOCOMOTIVE' SANDING CONTROL APPARATUS v I Filed April 29, 1941 2 Sheets-Sheet 2 "F igz INVENTOR CLAUDE M.HINE5 ATTORNEY Patented June 16, 1942 UNlTED STATE FATENT ()FF'ICE LOCOMOTIVE SANDING CONTROL APPARATUS Claude M. Hines, Pittsburgh, Pa., assignorto The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application April 29', 1941, Serial No. 390,892

4 Claims.

slip and thus to determine the most favorable.

time to begin sanding of the rails. As a result, the engineer may be compelled to use sand and sanding air too soon or in excessive amounts, in order to ensure against stalling of the train. On the other hand, when the locomotive is driven at a high speed, or in excess of seventy-five miles per hour for example, the engineer may be unaware of an incipient slipping condition of the drivers, with the result that the locomotive may be driven with excessive Waste of power for a long period of time. Another undesirable condition may be brought about if the engineer learns that the drivers are slipping and attempts to take the locomotive out of the slip by the unsafe practice of supplying sand alone, without quickly reducing the supply of steam orother power to the locomotive.

For a locomotive constantly operated under :service conditions in which these problems are encountered, it is desirable to provide anautomatic sanding control equipment including .means for operating a signal in response todriver slippage, and means for reducing or throttling the locomotive power supply while causing sand- .ing of the rails in time to avoid dangerous racing of the'drivers or loss of control of the locomoitive.

One object of the invention is to provide an automatic driver slip control apparatus for a traction vehicle comprising 'means operable to detect initial slipping of the drivers when accelerating power is applied thereto, and-further operable to effect the supply of sand in advance of the slipping drivers.

Another object of the invention is to provide an anti-driver-slip control equipment including means operative in response to initial slipping of a locomotive driver for energizing a signal device and for also actuating an associated sanding apparatus while efiecting a reduction .or throttling of the power applied to the driver.

A still further object of the invention. is. to provide a control equipment of the above description which may be adapted for use with various types of steam locomotives and electrically driven locomotives.

Other objects and advantagesof theinvention will appear in the following more detailed description thereof, taken in connection with the accompanying drawings, in which Fig. 1 is a schematic view ofone form of locomotive sanding control apparatusconstructed in accordance with my invention and associated with certain elements of a Diesel-electric locomotive; and

Fig. 2 is a schematic view of another embodiment of the invention in association with operating elements of a steam locomotive.

Apparatus, shoum in Fig. 1

Referring to Fig. 1 of the drawings, certain elements of a locomotive are thereinillustrated in diagrammatic form, including separate driver assemblies to and H, driving motors l2 and i3 arranged in operative relation with the driver assemblies, respectively, a controller 14 for gov-- erning the power supply to the driving motors, and a suitable source of electrical energy such as a generator l5 and a Diesel-engine l6. 7

The locomotive is equipped with fluid pressure actuated sand supplying means, comprising sanders 22 and 23 which are adapted to deposit sand in advance of the respective driver assemblies) and il when the'locomotive is operated to the left, as viewed in Fig. 1, and similar sanders 24 and 25 which are solocated as to supply sandin advanceof the two driverassemblies whenthe locomotive is moving in the opposite-direction.- For controlling the operation of the sanders there is provided an electro-responsive sandingicone trol valve device 21,,which is normally operative to control the supply of compressed air froma main reservoir 28 by way .of. a supply pipe;;29 to a sanding reservoir 3%. ,The sanding control valve device 21 is also adapted lor. operation to effect the supply of compressed air;from the rese ervoir so to a sanding pipe;3 I which hasa branch 32 leading to the pair of=sanders22 and;23,.and another branchfiii. connected .to theothersanders 24 and 25. V

The branch pipes 32 and 33 are provided withnormally open cut-off valves 35' and 36, respectively, one-of -Which-can be heldin-cpen position whiletheother is closed, the operation of the valves being determined by the direction-in which the locomotive is operated. For controlling thecut-ofi valves-35-and36 there is provided an automatic direction selector switch llL -which compris-esa movable contact 4 I" that is operative in one position to maintain the valve 35 closed by energization of a magnet 42 through a circuit including the positive terminal of a battery 44, a conductor 45, the switch contact, the coil of the magnet, and a conductor 46 connected to the negative terminal of the battery. The movable contact M is also operative in another position, when the vehicle is moving in the opposite direction, to efiect closure of the valve 35 by energization of a magnet 48 through the medium of the same circuit.

As shown diagrammatically in Fig. 1, the driving motor l2, comprising a field winding 12 and an armature l2a, and the driving motor l3, comprising a field winding l3f and an armature 13a, are connected in parallel in a circuit which includes a conductor 5! having connection with one of the supply terminals of the controller E4, the respective motor windings, a conductor 52, a normally closed switch contact element 53 forming part of a power reducing switch 54, and a conductor 55 connected to the other terminal of the controller 4. The power reducing switch 54 is interposed in the circuit just described as a means for effecting quick reduction of the accelerating power applied to the drivers in response to slipping thereof, as hereinafter more fully explained, and comprises a magnet 58 adapted to beenergized for raising the movable contact element 53 out of engagement with a stationary contact element 59, and a resistor 61? which is disposed in shunt or parallel relation with the contact elements.

According to the invention, both the switch magnet 58 and the operating magnet of the sanding control valve device 21 are adapted to be energized by operation of a control relay 55, which comprises a pair of normally open contact members '65 and 6?, and a pair of opposed ma net coils H1 and H for actuating both contact members simultaneously. The coil H! is adapted to be energized by the counter-electromotive force developed by the motor 12, while the coil H is arranged for energization by the counter-electromotive force of the motor l3, the two coils being '50 disposed as to direct magnetic flux in opposite directions with respect to the magnetically responsive contact members 66 and 51. It will be understood that since the speed and voltage characteristics of the two motors are substantially identical, the resultant or total flux produced by the opposing coils i and H will normally be at a minimum. However, upon a sudden increase in speed of either of the motors, due to slipping of the corresponding drivers, the opposing fields of the coils 70 and H will be put out of balance, 50 that the increased flux produced by the over-energized coil will be effective to move contact members 65 and El to their respective circuit closing positions.

The relay E is also operative to control a signal lamp 15, which is adapted to be mounted in a convenient location in the locomotive cab and functions to indicate initial slipping of the locomotive drivers, as hereinafter explained.

Operation 0 f apparatus shown in Fig.1

It will now be assumed that the controller I4 is operated to supply current to the driving motors l2 and I3 by way of the motor circuit comprising conductor 5|, the motor field and armature windings, conductor 52, switch contact elements 58 and 59, and conductor 55, and that.

the drivers It and H are thereby operated to propel the locomotive toward the right, as viewed in Fig. 1. It will be understood that the directional control switch contact 4| will be accordingly positioned as shown for efiecting energization of the coil 42, thus closing the valve 35. The valve 36 is at the same time disposed in its normal open position, so that the sanders 24 and 25 in advance of the drivers are conditioned for operation.

So long as the driver assemblies l0 and II are rolling along the rails without slipping, the driving motors l2 and 13 are operative at the same speed and consequently develop identical counter-electromotive forces. It will be understood that the current supplied to the coil 10 is a measure of a counter-electromotive force developed in the motor l2, while the current supplied to coil H is likewise a measure of the counter-electromotive force developed by motor I3. Each of the opposed coils thus tends to produce a flux substantially balancing that produced by the other, so that the resultant or total flux acting on the relay contact members 66 and 61 is thus maintained at a minimum. While this condition prevails, the contact members 66 and B1 are permitted to remain in their normal or open positions, as shown in the drawings.

If either of the locomotive driver assemblies l5 and II begins to slip, however, the load of the corresponding driving motor is quickly decreased with the result that the motor is free to operate at increased speed, and to develop correspondingly greater counter-electromotive force. When one of the coils 10 or H thus receives greater energizing current than the other due to the increased counter-electromotive force produced by the motor operating the slipping or racing driver assembly, the equilibrium of the flux forces acting in the relay 65 is upset, and the contact members 66 and '61 are quickly moved to their respective circuit closing positions.

Operation of the relay 65 causes energization of the power reducing switch 54 by way of a circuit which includes the positive terminal of the battery 44, a conductor 80, the relay contact member 66, a conductor 8|, the coil 58, a conductor 82, and the conductor 45 leading to the negative terminal of the battery. Upon energization of the coil 58, the contact element 53 is moved away from the stationary contact element 59, thereby connecting the resistance 60 into the circuit through which power is supplied to the driving motors I2 and 13. The driving torque developed by the driving motors l2 and I3 is thus automatically reduced in time to check the tendency of the drivers to slip or race.

At the same time, movement of the relay contact member 61 into circuit closing position establishes a circuit for energizing the electroresponsive sanding control valve device 21, which circuit comprises a conductor 84 connected to the positive terminal of the battery 44, the contact member 61, a conductor 85, the magnet winding of the sanding control valve device, and a conductor 85 leading to the negative terminal of the battery. The operating elements of the sanding control valve device 27, not illustrated in detail, are thereby actuated to effect supply of air under pressure from the reservoir 30 through the pipe 3! and the open valve 36 to the sanders 24 and 25, which are thus rendered operative to supply sand in advance of the driver assemblies.

The relay contact member Bl is also efiective to establish a circuit for the signal lamp 15, which circuit is energized by current from the battery 4 4 by way of the Contact member, a conductor 8] connected to the lamp, and the conductors 8 2 and 45. The locomotive engineer is thus made aware of the slipping condition developed by the drivers and of the automatic operation of the sanding control apparatus, and may then take such steps as would be deemed necessary to ensure proper control of the locomotive.

It is normally to be expected that the operation of the sanding control apparatus to supply sand to the rails and to reduce the supply of power to the locomotive driving motors as just explained will quickly cause retardation of the slipping driver assembly, until the rotative speed thereof has been brought back to approximately the speed of the other driver assembly. With the driver assemblies and the driving motors associated therewith again operating at substantially identical speeds, it will be apparent that the opposing coils Til and II of relay 55 will receive substantially equal energizing currents, thus permitting the movement of the contact members 66 and t? to the circuit opening position as shown in Fig.1. The switch 54 is thereby rendered operative to shunt the resistant 60 out of the motor supply circuit, while the magnet of the sanding control valve device 2? is deenergized to effect termination of the supply of compressed air to the sanders.

Equipment shown in Fig. 2

In Fig. 2 of the drawings there is illustrated a dilrerent form of locomotive sanding control apparatus embodying my invention, the equipment being in this case adapted to be carried associated with the driver assemblies, are similar in structure and function to those elements bearing like reference characters in Fig. l of the drawings. The equipment shown in Fig, 2 further comprises a steam supply pipe through which steam for driving the locomotive is conducted, a fluid pressure responsive steam throttle valve device 9i interposed in the supply pipe, a magnet valve device 92 for controlling operation of the throttle valve device, a relay 95 adapted to detect slipping of a driver assembly, and a direct current generator 95 which is operatively connected to the driver assembly It.

The steam throttle valve device Si is not illustrated in detail, but will be understood to comprise valve means which normally permits unimpeded flow of steam through the pipe 9!} to the locomotive cylinders at the rate determined by the usual engineers throttle valve, not shown. The throttle valve device 9| is operative by compressed air supplied to the device through a pipe I80 to reduce the flow of steam through the supply ipe. The magnet valve device 92 comprises a casing having a valve chamber Hi2, which communicates with the compressed air supply pipe 29 and has mounted therein a valve It? that is adapted to control communication from the valve chamber either to the pipe 2 9 or to an atmospheric vent port N54. The valve M13 is normally held in an upper seated position by the force of a coil spring I65, in which position the valve maintains closed the communication between the supply pipe 29 and valve chamber I62. The valve device is provided with a magnet I65 which functions, when energized, to effect movement of the valve I33 to a lower seated position in opposition to the force of the spring I05, for thereby effect.- ing supply of air under pressure through the pipe [0B to the steam throttle valve device 9!.

According .to the invention as embodied in the apparatus shown in Fig. 2, the control relay .95 comprises movable contact elements Ill], III and H2, which are operative to control the supply of electric current from a battery H3 to the signal lamp I5, the magnet valve device 92, and the sanding control valve device 2], by way of circuits hereinafter described. The switch contact elements Ht, III and H2 are operably assoe ciated with a pair of electro-responsive magnets H5 and H6, the latter of which constitutes a holding magnet that is arranged for energization independently of the magnet lit.

The magnet I 55 is adapted to be energized by current supplied by the direct current generator 96 through a circuit which includes a conductor H8, the coil of the magnet H5, a conductor H9, a condenser I29, and a conductor I2I connected to the other lead of the generator. As will hereinafter be explained, the current energizing the magnet H5 is at all times a measure of the rate of change of speed of the driver assembly It associated with the generator.

As disclosed in Fig. 2 of the drawings, the sanding control valve device 21 is arranged to control the supply of compressed air from the supply pipe 29 through a pipe I25 to the sanding reservoir Sta, which in this case constitutes a timing reservoir having a predetermined volume. Associated with the timing reservoir 30a is a pneumatic switch device I25, which has a movable contact element I 27 that is adapted to bridge a pair of contact elements I23, and suitable piston means, not shown, for holding the contact element I21 in circuit closing position so long as the pressure of air in the timing reservoir remains above a minimum value. It will be understood that the timing reservoir 36a is adapted to be charged with sufficient air under pressure to cause operation of the associated sanders for a definite interval of time, as determined by the class of service for which the sanding apparatus is desired.

Operation of equipment shown in Fig. 2

When the locomotive sanding control apparatus is conditioned for operation, compressed air is supplied in the usual manner to the supply pipe 29, from which air is supplied by way of sanding control valve device 2? through the pipe I25 to the sanding or timing reservoir 38a and also to the pneumatic switch device I25. With the magnet valve, device 92 in its normal deenergized condition, the valve element Hi3 therein is positioned for venting to atmosphere the pipe IE!!! communicating with the steam throttle valve device 9I. The throttle valve device 8! is consequently held in its normal fully open position for permitting supply of steam atany desired rate by way of the pipe 95 for operating the steam locomotive.

Assuming that the locomotive is set in motion, one or the other of the cut-off valves 35and 36 is automatically closed in the manner explained in connection with Fig. 1, so that only the sanders in advance of the locomotive driver assemblies remain in condition for operation.

As the speed of the locomotive is increased, the direct current generator 96 is operated by the driver assembly Iii to supply current through the circuit including the conductor IE8, magnet H5, conductor H9, condenser I25 and conductor I 2|,

it being understood that the current flow in this circuit is determined by the rate at which the condenser receives a charge of electrical energy and consequently by the rate at which the driver actuated generator is accelerated. Thus when the vehicle is operated at constant speed, the voltage of the generator 96 and of the condenser I20 remains constant so that there is at such time no flow of current in the circuit.

According to the invention, the magnet H5 is constructed and arranged to produce a small and ineffective magnetic force when energized by the relatively low current supplied to the circuit while the locomotive driver assembly and the generator 96 are accelerated at a normal rate. The locomotive may thus be accelerated under normal operating conditions, or so long as the drivers are operated in non-slipping relation with the rails, without causing operation of the relay 95.

If the driver assembly I9 should commence to slip or to race with respect to the rails, however, the speed at which the direct current generator 96 is operated is consequently increased at an excessively rapid rate, so that the resultant current flowing in the condenser circuit becomes high enough to cause efiective energization of the magnet I I5. The relay 95 is thereby actuated so that the movable contact elements III], III and H2 are shifted to their respective circuit closing positions. The relay 95 is then maintained in operative position due to energization of the holding magnet H6 by way of a circuit which includes the positive terminal of the bat' tery H3, a conductor I3I, the switch contacts I21 and I23, aconductor I32, the winding of the magnet H6, a conductor I33, the switch contact element I I0, and a conductor I35 connected to the negative terminal of the battery.

At the same time, current is supplied to the signal lamp I5 through a circuit comprising a conductor I3'I connected to the positive terminal of the battery H3, the lamp, a conductor I38, the conductor I33, switch contact element III] and conductor I35.

Movement of the contact element III to circuit closing position results in energization of the magnet of the sanding control valve device 21 by way of a circuit including the conductor I3I, the connected switch contacts I21 and I28, conductor I32, a branch conductor I40, the winding of the sanding control Valve device, a conductor II, and the contact element III which is connected to the conductor I35 leading to the negative terminal of the battery. The sanding control valve device 2? is consequently rendered operative to efiect the supply of compressed air from the reservoir 35a by way of the pipe I25 to the pipe 3!, from which the air is delivered to the sanders in advance of the locomotive driver assemblies. I

Meanwhile, with the relay contact element II 2 in circuit closing position, the magnet portion Hit of the magnet valve device 92 becomes energized through a circuit which includes the conductor I3I leading from the battery, the contact elements I21 and I23, a conductor M4, the magnet Winding, a conductor I45, and the contact element H2 and conductor I35 leading to the negative terminal of the battery. Upon energization of the magnet in the magnet valve device 92, the valve W3 is moved to its lower seated position, thereby cutting off communication between the valve chamber I52 and the atmospheric port I04 while establishing communication from the supply pipe 29 through the valve chamber and pipe I00 to the fluid pressure responsive operating portion of the steam throttle valve device 9|. This valve is thus actuated to reduce the flow of steam for operating the locomotive.

It will thus be seen that the sanding control apparatus shown in Fig. 2 is adapted to be rendered operative in response to the development of an initial slipping condition of a locomotive driver assembly for quickly reducing the power applied to the drivers and for supplying sand to the rails, so that the tendency of the drivers to continue to slip or to race is counteracted automatically. The locomotive engineer, having been informed of the slipping condition of the drivers by operation of the lamp I5, can then take further steps to regain control of the 1000- motive.

When the pressure of air with which the timing reservoir a was originally charged has been reduced to a predetermined value, due to the operation of the equipment as thus explained, the pressure responsive switch device I26 is rendered operative to break the connection between the movable contact element I21 and the stationary contact element I28, thereby opening the circuit for the magnet I 05 of the magnet valve device and the circuit for the magnet of the sanding control valve device 21. The holding magnet H6 is at the same time deenergized for permitting movement of the contact elements H0, III and H2 to their respective circuit opening positions. It will of course be understood that the magnet I I5 is also efiective- 1y deenergized, since the racing condition of the driver assembly Ill has by this time been corrected and the generator 95 is consequently not operated at a rate effecting flow of appreciable charging current in the condenser circuit. The various elements of the sanding control apparatus are thus returned to the normal condition within an interval of time determined by the volume and pressure of air in the timing reservoir 300..

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In an acceleration control system for a steam driven locomotive having a steam supply conduit and driver means, in combination, steam throttle valve means operative to reduce the flow of steam through said supply circuit, electro-responsive means for causing operation of said throttle valve means to reduce the supply of steam to the locomotive, electro-responsive sanding control means assoicated with the driver means of said locomotive, an electro-responsive relay device operable to effect energization of the first mentioned electro-responsive means and said electro-responsive sanding control means, and electrical energizing means operable by said driver means to effect operation of said relay device when a slipping condition of said driver means is indicated.

2. In an acceleration control system for a locomotive including prime mover means and driver means operable thereby, in combination, fluid pressure responsive sanding means for said driver means, electro-responsive sanding control valve means governing the supply of fluid under pressure for said sanding means, electro-responsive propulsion control means operable to reduce the energy available for operating said prime mover means, an electro-responsive relay device operable to efiect energization of said sanding control valve means and said propulsion control means, a direct current generator driven in accordance with the speed of the locomotive driver means and arranged to produce a voltage that is a measure of the speed thereof, and current controlling means including a condenser interposed in series relation between said generator and said electro-responsive relay device, whereby said generator is rendered efiective to supply sufiicient current to energize said relay device only when the acceleration of said driver means is at a slipping rate.

3. In an acceleration control system for a steam driven locomotive including steam sup ply means and driver means, in combination, a steam throttle valve device operable to control the supply of steam from said supply means, electro-responsive actuator means for said throttle valve device, electro-responsive sanding control means associated with said driver means, a relay device operable when energized to effect energization of said actuator means and said sanding control means, a generator operable by said driver means, and means connected between said generator and said relay device for effecting a current supply to said relay device that is a measure of the rate of change of the speed of said generator.

4. An acceleration control system operable to check slipping of the driver means of a locomotive during propulsion thereof, comprising electroresponsive sanding control means, electroresponsive propulsion controller means operable to limit the power applied through the medium of said driver means, a relay device operable to effect energization of both said sanding control means and said propulsion control means, means for conditioning said relay device in accordance with the rotative condition of said driver means, and means for limiting the time interval during which said relay device efiects energization of said elements controlled thereby.

CLAUDE M. HINES. 

